ITS Networking Practice Test 2026 - Free ITS Networking Practice Questions and Study Guide

Link-state routing protocols create and maintain a complete view of the network topology. Each router floods information about its directly connected links to all other routers, building a shared topological database. With this full map, every router can run a shortest-path algorithm to determine the best next hops, which helps achieve fast convergence when the network changes.

Open Shortest Path First is a classic example: routers exchange link-state advertisements, populate a link-state database, and then use Dijkstra’s algorithm to compute routes from the complete topology. This approach relies on having that full topology map to make accurate, loop-free decisions.

Other protocols don’t fit this description. RIP uses a distance-vector approach, sharing only hop counts with neighbors and not building a global topology map. BGP is a path-vector protocol focused on policy and autonomous systems, not a coordinated graph of the entire network. EIGRP is a Cisco-proprietary protocol that blends distance-vector elements with some link-state-like features, but it does not maintain a complete network-wide topology map the way true link-state protocols do.

So the protocol exemplifying a link-state approach with a full topology map is Open Shortest Path First.